When I use Obzedat Ghost Council as my commander in a 4 player multiplayer game, he keeps getting blocked by opposing commanders when they do not have flying/reach. This has happened in the last 2 games I've played, and has almost lost me a game or 2.

Here's what happens,
1. My commander Obzedat is exiled the turn before with Obzedat's ability.
2. My next turn he returns to the battlefield.
3. When I attack an opponent (for this particular case the opponent had their commander Samut, Voice of Dissent untapped)
Actual: Samut was able to block my commander
Expected: Samut does not have flying/reach and should not have been able to block Obzedat.
Samut in this case did not have anything equipped and no creatures/enchantments/artifacts that would have given it flying.